Restoring normoglycaemia by use of a very low calorie diet in long- and short-duration T2D
Steven S, Taylor R. Diabetic Medicine. Doi: 10.1111/dme.12722.
The Counterpoint study showed that a very-low-calorie diet (VLCD) can improve both beta-cell function and liver insulin sensitivity in people with type 2 diabetes (T2DM)<4 years duration. The hypothesis is that of an individual threshold above which fat deposition in pancreas and liver leads to the twin pathological defects of T2DM. This study explored whether reduction of the fat deposition was beneficial after longer diabetes duration. Twenty-nine patients (14 with T2DM>8 years, HbA1c 8.6% [70mmol/mol]) received a VLCD (624kcal/day) using liquid meal replacement formulae for eight weeks, having omitted their usual anti-diabetic medications. The long-duration group lost 13.9Kg (14.4% body weight) and fasting plasma glucose (FPG) fell from 13.4 to 8.4mmol/L, however, these averages hid marked heterogeneity; some individuals responded within one week, others not at all. In contrast, all of the short-duration group responded (87% achieving non-diabetic FPGs). Significant blood pressure and lipid improvements were consistent across the groups. VLCDs continue to be effective after years of T2DM but are unlikely become part of standard therapy as they involve a boring, socially-isolating regime, which will continue to limit adherence.
Comparative effectiveness of early versus delayed metformin treatment T2D
Romanelli R. Chung S. et al. Diabetes Research and Clinical Practice Doi:10.1016/j.diabres.2014.12.019
In the newly diagnosed type 2 diabetic, there is a lot of patient education and information to go through with the patient. One important aspect to clarify is at what point drug therapy such as metformin would be considered? According to the BNF (http://www.evidence.nhs.uk/formulary/bnf/current/6-endocrine-system/61-drugs-used-in-diabetes/612-antidiabetic-drugs) an initial three months (at least) of lifestyle and dietary management strategy should be pursued. This paper defined the initial stages as less than six months from the starting point. According to the findings of this paper, early treatment – defined as using metformin – was superior to delayed treatment (greater than six months). This was demonstrated by a lower HbA1c and BMI when the two treatment arms were compared. In addition, the early treatment arm patients were less likely to receive further additional therapeutic interventions. This may well be a reflection on the proven efficacy of metformin, a tried and trusted therapeutic agent often used first line. Although many patients will end up on some form of drug(s) therapy to help manage their diabetes, it is important to always bear in mind the critical importance of lifestyle intervention.
Safety and effectiveness of DPP-4 inhibitors versus intermediate-actingT2D
Tricco A. Antony J. et al. BMJ Open. Doi: 10.1136/bmjopen-2014-005752
We know that type 2 diabetes is a chronic and progressive disease and it may take more than one drug to bring about effective control. Even then this may not work and this review looked at a third line intervention (after 2 oral drugs) such as DPP-4 inhibitors or intermediate acting insulin. The main outcome studied was HbA1c but a number of other end points were also looked at. The literature search yielded 10 eligible studies though interestingly five of them were not published. Also no research article looked at the cost comparison of these drugs, an important consideration nowadays. The conclusion was “that DPP-4 inhibitors are superior to placebo and have similar effectiveness as NPH insulin in reducing HbA1c as a third-line therapy in patients with T2DM.” Of course, this is not the end of the story as we will need longer and well defined studies that examine not just HbA1c but mortality and morbidity from both the disease and interventions. Patient preference may also come into play, how many would prefer an injection or simply take an extra tablet?
Effect comparison of metformin with insulin treatment for gestational diabetes
Genxia L, Zhao S et al. Archives of Gynecology and Obstetrics. Doi: 10.1007/s00404-014-3566-0
Metformin’s glucose lowering, weight neutral and cardiovascular properties are well recognised. However, although its use is unlicensed in gestational diabetes (GDM) or in pregnant women with pre-existing diabetes, it is recommended by both the BNF and NICE in both these situations. There is increasing evidence to suggest that it has a positive impact on maternal and neonatal outcomes as highlighted in this meta analysis of 11 studies which compared its use with that of insulin. Out of the 11 studies examined, although there was no significant difference in glycaemia (based on HbA1c and fasting glucose), mothers in the Metformin group had significantly lower frequency of pregnancy induced hypertension, weight gain and gestation age at delivery. Compared with the insulin group, neonates whose mothers were treated with Metformin had lower birth weights, neonatal hypoglycaemia and admissions to neonatal ICU. This study provides further evidence for early use of Metformin in GDM and, given the increasing incidence of T2DM in women of child bearing age, its continuation when pregnancy is confirmed which is not often the case.
Discordance HbA1c and GTT for postpartum exclusion of diabetes following gestational diabetes
Duke A, Yap C et al. Diabetes Research and Clinical Practice. Doi: 10.1016/j.diabres.2015.01.006
Gestational diabetes (GDM) is a known risk factor for Type 2 diabetes (T2DM). Indeed NICE guidance currently recommends post partum testing in the form of a fasting glucose. Whilst other ways of screening for T2DM, including HbA1c and oral glucose tolerance test are also in clinical use in this group of patients, there is often poor concordance between tests. Indeed, this paper found that, at 6-12 weeks post partum there was only 54% concordance between them. This is probably because each test examines different aspects of glycaemia – the OGTT looking at post prandial glycaemia whilst HbA1c at fasting glucose (especially when >8.5%). Whilst this paper recommends using the OGTT to screen patients post partum, this is contrary to NICE guidance. It is likely that checking fasting glucose will miss some patients with abnormal glucose tolerance post partum. However, given that they are high risk, long term surveillance is usually recommended.